This invention relates to containers, specifically to those containing the biodegradable plant waste called compost and to devices which facilitate rapid composting, or reduction of yard waste to the organic material called humus.
Many states have legislated the reduction of solid waste collected at public landfills. One such waste is yard waste such as grass clippings, leaves, and twigs. Composting is a natural, inexpensive solution to reducing the amount of yard waste collected in landfills, yet the majority of the public prefers not to do this process.
One reason for public apathy about composting is that present containers and technology are not compatible for today's high volume demands. Instead, presently available containers are designed for increasing existing fruit and vegetable harvest, and disposing of the organic matter that is not edible. Existing compost containers are viewed as producing a rotting mass of wet matter that has an unbearable odor.
Current compost bins look like their predecessors of thirty years ago. Many gardening magazines still embrace the old ways for instructing the consumer on building composting systems. Quite frequently, the stationary wooden slat or stationary wire mesh frame type container is still advertised as being "most desirable". Though the cost of these types of containers is low, consumers do not prefer them over newer, more aesthetic designs. Previous containers frequently lack any artistic styling and appear like oil drums, or cardboard boxes, or a stack of wooden pallets. These drawbacks in appearance discourage widespread consumer use, because the consumer is not able to hide an unsightly container.
Existing stationary compost bins produce an output product that is usually a wet mass of large clumps of semi-decayed matter combined with whole undecayed matter. This wet matter is then inefficiently separated with hand tools to break up the clumps into smaller clumps. Existing rotary containers offer a slightly more efficient process in reduction of clump size but are generally lacking in pleasing visual consumer appeal.
Existing compost containers were not designed to process compost though the use of microbe enriched catalysts. These catalysts can only by optimally utilized if the three major factors of moisture content, oxygen availability, and thermal drain are precisely balanced. Most stationary containers ignore the need for oxygen availability and moisture balance. Most rotary containers ignore the need for reducing thermal drain. Open stationary containers allow too much moisture fluctuation to occur due to being rained upon or allowing excess evaporation to occur.
Previous compost bin designs, both stationary and rotary, are now being redesigned with a rigid foam laminate for the purpose of insulating the hot composting mass from the cooler outside ambient temperatures. Insulating does promote a warmer environment for bacteria, and increases the rate of chemical reaction, but laminates are not as thermally efficient as air gap insulative design.
Presently, there are stationary compost containers that have air gap design, but are not capable of being rotated to break up wet clumps of humus into the smaller desired particle form; nor are those stationary air gap containers portable, which affects their convenient use. Since the stationary containers must be opened to be mixed and separated, internal temperature falls, and reaction rate reduces. There are rotary containers without gap design. They are mostly cylindrical, and most are to be located in an isolated, out-of-sight location for use, and are not portable.
Stationary containers do not offer the ability to break up large clumps without opening the container with resulting heat loss. The large clumps are two to five times more dense than surrounding material and consist of up to seventy percent minerals and compounds, and less than fifty percent fiber. The potential quantity of heat energy within a clump is two to five times that of the surrounding material. Thus the clumps can act as heat sources and can distribute heat extensively to the surrounding bacteria colonies, if broken up into smaller clumps without losing heat to the container exterior. Existing rotary containers break up these large clumps into smaller clumps but lose heat to the container exterior due to being under insulated. Stationary containers have a notorious hot spot, and subsequently have cool, low activity areas within, making compositing in the stationary container a less uniform and consequently longer process.
Previous rotary containers contain internal structures for aiding in mixing when the container is rotated. These structures do not provide a path from the core of the biomass to the container exterior for concentrations of gaseous reaction by-products to escape, or for a new supply of atmosphere to enter and react. Absence of this pathway when the rotary container is stationary, does not facilitate maximum biomass degradation. Therefore, existing enclosed rotary containers that only stir when rotated, will prematurely convert an aerobic reaction to anaerobic reaction, which is undesirable. Aerobic reactions are very desirable since they react up to sixteen times faster than anaerobic reactions, and the biproducts of aerobic reactions are primarily carbon dioxide, an odorless gas, instead of the odorous methane and ammonia. Existing stationary compositing containers complete between thirty-five and seventy-five percent of their compost cycle in an anaerobic reaction which explains their notorious bad smell.
Prior art containers, due to shape and construction materials, and size, do not appear in large quantities on the store shelves of retail department stores despite their low cost. This prevents the growth of composting as a widespread waste reduction method. Such stationary containers are marketed in boxes dimensionally as large as fifteen inches by thirty inches by thirty-two inches or larger. This size is usually too large to appear on retail department store shelves. Many rotary containers are made of metal and are of substantial weight, e.g. greater than forty pounds, which is too heavy for stocking on retail shelves.
Previous composting containers are inadequate for today's applications in the following ways:
a) stationary types do not process a volume high enough to keep up with weekly grass clipping volume,
b) stationary and rotary types frequently are too unsightly in appearance to gain large public appeal,
c) stationary types require tedious hand mixing where the operator of the container is thoroughly exposed to the odorous gases within the device,
d) both stationary types and rotary types are usually not portable,
e) many previous containers were not able to utilize today's microbe enriched catalysts and thus were not designed to precisely balance moisture content, oxygen availability, and thermal drain,
f) previous containers are not in the shape of an insulated sphere which makes them less effective at redirecting heat back into the reaction biomass,
g) previous insulated containers use foam laminate type insulation which is about thirty percent as effective as air gap type insulation,
h) previous containers have no structures to create air/gas passages or air/gas exchange areas completely to the core of the biomass within, thus operating primarily in the undesirable anaerobic state,
i) previous containers were not designed for compact lighweight packaging such as is necessary to facilitate stocking of large volumes of the containers on common retail department store shelves.